1. Field of the Invention
The present invention relates to vehicular suspension systems. More particularly, the present invention relates to a structure for advantageously disposing a driven sprocket or a brake disc on a vehicle in relation to the suspension system.
2. Description of the Background Art
A known suspension structure is constructed as follows. The structure includes a final drive case of an independent suspension system supported between left and right vehicle body frames. A suspension arm forming part of the independent suspension system is disposed outward of a corresponding one of the left and right vehicle body frames. Further, a driven sprocket and a brake disc are coaxially disposed on either side of the final drive case and outside the corresponding one of the left and right vehicle body frames. Such a suspension structure is disclosed, for example, in Japanese Patent Laid-open No. Sho 63-90486.
A suspension arm is one of several members that form a suspension system. The suspension arm is disposed on a vehicle body frame around a final drive case. If, in this circumstance, a driven sprocket or a brake disc is further disposed outside a vehicle body frame, there is a need to dispose (circumventive disposition) or structure (circumventive structure) the suspension arm so as to extend around or circumvent the driven sprocket or the brake disc. The circumventive disposition, however, leads to more restrictions imposed on vehicle layout. The circumventive structure requires that a relief structure be disposed in the suspension arm. This relief structure hinders sufficient rigidity, and thus weight is increased to achieve sufficient rigidity. It is therefore an object of the present invention to provide a suspension structure that requires no such circumventive disposition or circumventive structure.